Here's a dumb question. What do you do with the back side of body panels when restoring?

Situation: As part of this winter's restore, Ms. Jenavieve's fenders will be coming off to be replaced with the much better ones I removed from my parts car. The "new" fenders appear to still have the factory paint on them. I will be starting to prep them in the next couple weeks for the transplant, and it occurred to me that I had no idea what the "proper" way was to paint the back side (the side you can't see). The idea is to have them completely stripped, prepped, and primed before mounting them, so obviously I have to do something with the back side before they get mounted.

What's the usual procedure? Complete paint with body color? Just prime the backside good and leave it? Spray some sort of weatherproofing on them? Obviously I don't really care what the backside looks like, but it needs to have something to protect the metal.

By the way, Brett (if you see this) I think we might have talked about this when I visited you this summer, but if we did I don't remember what your suggestion was. I really need to start writing things down.

Well on two of my cars here that are still somewhat original they have the protective coating still on them.

If you strip the fenders down to bare metal I would prime, cover with a black topcoat and then apply a good protective undercoating. Don't leave them in primer. Primer doesn't offer the protection a good topcoat does.

If you will never drive the car in the rain or snow you could skip the waterproofing but it's an extra layer of protection against the elements, stones, dirt and road debris.

Have to go with Art on this, I painted mine inside as well as the jams so they would match when I paint the car off when it is together, (hopefully). I also took a gallon of rubberized roofing tar poured out some of the liquid that had seperated from sitting on the shelf, and replaced it with kerosene, mixed it up well and brushed it all over the inside of the fender a nice thick coat. Why kerosene ?? it allows the tar to dry faster so you do it one day and it's dry to the touch the next, once its bolted up and gaps adjusted I then go in and coat all the contact areas to seal them up as well.

Not saying this works for everyone but from prior experience it works for me.

Thanks Brett! The tar and kerosene was what I remember talking about. I knew we had discussed this.

I thought about painting the fenders before mounting them, but I'm worried about all the paint matching so I think I'm better off stopping at the primer stage for the exposed parts of the panels and then shooting the assembled car all at once. I will be painting the doors, hood, and trunklid (bonnet and boot?) while they are removed just because I don't want to get too crazy with the masking etc. and because I don't want to leave any spots unpainted, but those can be painted at the same time as the rest of the car. The fenders, on the other hand... I want those mounted before they get painted so that I don't have to worry about dinging up my nice new paint job when remounting them (I remember how much fun they were to remove).

I left the outside of the fender in primer and only painted color on the inside and "jams". so that when everything is back in place and I'm ready to paint the whole car I dont need to be opening doors and such to paint that off as well.

Brett, that's kind of what I was thinking with the fenders, though I will be painting the doors while they are off (at the same time the rest of the car gets painted, so color match shouldn't be an issue) and then remounting them afterward. Those I think I can mount safely without dinging up the paint. Same with the hood and trunklid. That way I can paint the jambs etc at the same time.

jcdean, that was my first thought for the inside of the fenders... some sort of truck bedliner.

My opinion is you will be better off in the long run with the doors mounted and adjusted before you paint the car. The doors are heavy and awkward. The chance of getting them aligned the first time is slim. Less chance of having to go back and fix scratches.

All good to know. That's why I defer to those who have been there. I just figured it would be easier to mask to paint the jambs, basically just sealing off the interior, if the doors weren't mounted.

Having said that, what works well to seal the gap between the door and body for masking purposes (so the weatherstrip and door latch doesn't get overspray, etc? I would think maybe some kind of foam rod jammed into the gap?

What I have done and most of the pros I know do is mask the car and then spray the engine compartment, trunk compartment, door jambs and the sides and bottom of the doors and door hinges. Include the bottom of the hood and trunk lids and their hinges here. You can also spray any of the interior that might be left exposed. But most of the interior will be covered with sound deadener, carpet and vinyl. This gets all the areas that will be covered when the exterior of the car is painted.

This gives you the benefit of seeing how the paint flows with your gun based on the current temps, etc. so you can make any adjustments before you spray the exterior. If there are any areas or spots that might need fixing, fix those now. After the paint dries remove the masking paper and assemble the car. Get all the gaps right and bolts tightened. Having the car body higher up helps in painting the lower parts of the car. I made a rolling frame the body sits on that puts the bottom about 18 inches off the ground.

Now mask the car again with new paper and plastic. You do not want old paint or stuff coming of the old paper into your new paint. For masking around the doors now, use 3M Door Aperture Tape. It helps prevent a "tape line" between paint times. Clean and prep your spray area, wipe down the car a final time, mix the paint and spray.

The interior of the car, trunk and engine bay are painted, covered and protected. After the paint dries, remove the masking paper and you can cut and buff if needed. The car is painted. No messing with hanging the doors and worrying about nicks and scratches or worse. Let the car and yourself rest for a couple of days. Cover the car with auto paint grade plastic to keep clean.

Now you can finish putting the car together. For me I found it best to install the brake and fuel lines, wiring harness, dash and sound material and carpet while the car was higher off the ground. Less bending over and easier access to the under side of the car. Put the body on jack stands and install the rear axle and suspension. Don't fully tighten the bolts until the car is completely assembled and all of the weight is there.

Line up the engine and trans, raise the front of the car and slide engine/trans in place. Slowly lower the body while aligning the front suspension top mounting bolts. Having someone to help guide the shift in place will be good. Install drive shaft. Finish connecting brake and fuel lines. Finish wiring and all the other things that need to be completed. Start and drive car with big grin on face.